* Add Rails 5.2 support.
* Add rails-5-2-stable specific gemfile and adust exclusion pattern for travis
* Revert Gemfile to original state.
* Update default Gemfile to latest rails (5.2) and latest country_select (3.1.1).
* Revert rubocop in gemspec. Add Ruby 2.5.0 to the travis test set.
* Allow older versions of railties.
* bundle update. add back activemodel requirement.
* Update Rails from RC2 to stable.
* Update gemfile.lock
* remove rails upper bounds from gemspec. rely on latest versions in gemfile
Bijan Rahnema